GB1291790A - Tube bending machine control - Google Patents

Abstract

1291790 Angular bending MC MACHINES Ltd 5 April 1971 8702/71 Heading B3E [Also in Division F2] A rotary control valve for a tube bending machine has a fixed body 128 to which are connected an inlet 130 and a plurality of circumferentially spaced outlets 78. Mounted within the body is a rotary element 132 connected to a selector 138. Annular grooves 142, 144 and passage 146 in the element and passage 148 in the selector communicate the inlet to the selected one of the outlets 78. Circumferentially spaced through holes in the selector communicate the remainder of the outlets to atmosphere. In use the selector is connected to the turret of the machine and each outlet is connected to a respective one of a plurality of piston-cylinders 76 which operate locking heads 72. Each of the latter co-operate with a notch in a disc 70 mounted on a rotary shaft 68 on a carriage 100 which runs on wheels 92 along rails 26, 28 that can be moved laterally by rack and pinions 32, 34. The carriage carries a tube gripping collet 98 which is actuated by piston-cylinder 106, 112 and is rotatable with the shaft 68. Each disc 70 is diametrically split and is lockable on the shaft 68 by a screw extending across the split. Prior to bending each disc is locked on the shaft in a predetermined angular position which represents a required angle of plane of bending and is measured by a scale and vernier 120, 124. After the tube has been gripped by the collet 98 the carriage is moved so that a spring-loaded non-return detent 82 rides over a first step 40 along the side of the rails and abuts its rear surface. The turret is then rotated to cause the valve to admit pressure to the first piston cylinder. The shaft 68 is then rotated until the locking head 72 enters the notch in the first disc 70. The tube is now in the required plane for bending. After bending the carriage is moved so that the detent 82 abuts the second stop 40 and the turret and shaft 68 are respectively rotated to position the tube in the second required plane for bending as before. Abutment of the carriage with an end stop 44 automatically returns the carriage. The valve and control system may be used to cause locking heads to hold the carriage in predetermined longitudinal positions and/or to automatically control the angle of bend.